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Was there an "Eve"?

SkepticalScience

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I once recall reading a science mag that pointed to the observation that the entire human race had one mother and several different fathers.

I read it many years ago while i was a kid, and am wondering if anyone here has heard about it before; and what the specifics were.

The only thing I remember, was that it was a "log proof" of sorts. . . and it concluded that we must all come from one female but could have had many different fathers.

Thanks!
 
This is probably about the issue of mithocondrial DNA. Mitochondria are the organelles responsible for energy production in our cells. They are quite complex organelles (according to the endosymbiotic theory they were originally independent procaryote, no nucleus, cells) and have their own DNA.

This DNA is a different sequence from the one you can find in the nucleus. And it comes just from the mother, from the mithocondria in the ovulus (while, of course, nuclear DNA comes from both parents) So everyone's mithocondrial DNA would come from the same woman...
 
Yes, I do remember the article mentioning mithocondrial DNA.

But, they had this neat "proof" of sorts. . .and I want to read it again, and see if I was duped as a child. Also, what is the current prevailing wisdom on all people having the exact same maternal ancestor.

One webpage I just found sort of has it:

a) You were directly descended from 2 parents, 4 grandparents, 8 great-grandparents, 16 great-great grandparents and so on.

b) So, as you go back in time, the number of your ancestors increases.

c) Go back far enough and you’ll find millions of forebears in your personal lineage.

d) The same, of course, is true for everyone else. But as you go back in time the total population of the world decreases, meaning that the farther back you look, the more likely you are to encounter someone who was a common ancestor of any two random people alive today.

Therefore the question then becomes: How far must you go back in time to find someone who is a common ancestor of everyone alive today? And for bonus points, who might that have been?

What do you think of that??
 
It's possible that everyone alive today is descended from one woman. This would not necessarily make her the First mother of mankind. It simply means that her contemporaries have no living descendants.

Google Brian Sykes- "The Seven Daughters of Eve".
 
I think there was something about the lowest our ancestors' population ever got was a few thousand people around 75,000 years ago.
 
It's more complicated than all that. The first impression could be that there is a Mithocondrial Eve and a Y chromosome Adam...

But let's think as an example of Pitcairn's Island, the one were the Bounty mutinies ended. (The story, briefly, is as follows:
there is a mutiny in the Bounty, led by Christian Fletcher against captain Bligh. The mutinies flee, take women from some island and end at Pitcairn. All the inhabitants are descendants from the ship's sailors and the captured women)

Today all of them have the same surname: Fletcher. Does this mean Fletcher was the only father? No, let's see what happened:

To the island came sailors with diferent surnames and all of them were fathers of their children. With the passage of time a surname produced only daughters and disappeared.

Then another one produced only daughters and disappeared too...

That repeated several times resulted in all of them being called Fletcher. That's their name and implies that they are his descendants in some way, but through a complicated path which doesn't mean that the others have not left descendants or that their gene pool has been lost. The surname is lost, not the genes.
Fletcher doesn't have anything special.

Translated into genetics: if a man has only daughters, his Y chromosome is lost, if a woman has only sons, her mitochondrial DNA is lost.

with time, this results in a single mitochondrial Eve and a single Y chromosome Adam, given that the original population is small. It seems to be the case that mankind consisted in an undetermined time in the past, after a loss of population (maybe some 150 000 years ago) of only 10 000 - 100 000 people, which allowed the apparition of these characters (Mit. Evea and YCA) but that doesn't mean they have something special.
 
Fendetestas said:

Translated into genetics: if a man has only daughters, his Y chromosome is lost, if a woman has only sons, her mitochondrial DNA is lost.
Click to expand...

Um,.... no. Boys have mitochondria, which they get from their mothers, just like girls. Mitochondrial DNA cannot be "lost" unless there are no living descendants.
 
new drkitten said:
Um,.... no. Boys have mitochondria, which they get from their mothers, just like girls. Mitochondrial DNA cannot be "lost" unless there are no living descendants.
Click to expand...

Wouldn't her mitochondrial DNA be lost if she only has a son, who only has sons?
 
shanek said:
Wouldn't her mitochondrial DNA be lost if she only has a son, who only has sons?
Click to expand...

Yes, you're right (and I'm wrong); I was looking at it one generation too soon....
 
Wouldn't her mitochondrial DNA be lost if she only has a son, who only has sons?
Click to expand...

If she only has a son, and he in turn has a daughter the mitochondrial DNA is lost just the same (her son has it, but her grandaughter doesn't).
 
Prime energy>>Matter+energy>>sub atomic particles>>atoms>>molecules>>complex molecules>>first living cell>>tissues>>complex living beings>>humans...so on. It can be one model of evolution. What from then we all come from basically?
 
...hmmm well, that clears it up.

Fendetestas- nice explanation.

Skepticalscience-Sykes has a book on y chromosome tracing too.
 
Soapy Sam said:
It's possible that everyone alive today is descended from one woman. This would not necessarily make her the First mother of mankind. It simply means that her contemporaries have no living descendants.

Google Brian Sykes- "The Seven Daughters of Eve".
Click to expand...
It's a fact that everyone (every human, that is) alive today is descended from one woman.
 
Mother is soure of our prime energy (mitochondria in ovum). Male female joined DNA in fertilized egg takes energy from it. So our prime soure of energy is maternal/ladies.;) But in physical human sense, we can't say all are born from one lady as male DNA is also there unless female's clone. Anyway females can only be cloned by taking single woman but male clone can only be formed by taking both male & female. This aspect can be just thought.
 
Dragon said:
It's a fact that everyone (every human, that is) alive today is descended from one woman.
Click to expand...
How do you figure? I can see that if there was a bottleneck in our ancestors' population, that a single Eve would be possible, but I don't see any reason that it would be required.

You could have had a population of thousands of apes who came out of the trees, and this population led to thousands of Homo Erectus, which led to a population of thousands of Homo Habilis, etc., until you arrive at the advent of reality TV shows. I don't see any reason why it would be necessary to have a single eve, going back to the time of single-cell organisms.
 
I seem to remember that mitochondria were little lifeforms of their own who a billion years ago just happened to get themselves mixed up in all this crazy big multicellular life business.

Basically, they just went and got a job in the big city. :D

But are they "our" mitochondria or are we just "their" home city?

Hmmm... ;)
 
Well, the mitochondrial DNA story does mean that we all have one uniform mother (including the son of the son's perspective, which could only argue that there may not have been one "Eve"). But, if you look at the mitochondrial DNA, this proves that we descended from a "single Eve", so to speak.

Here's the potential problem... (which may or may not have already been answered, but would be an interesting follow-up and addendum to this story)

What exact sequence of DNA in mitochondria did they look at? Was it a gene sequence? Was it a bit of intron? How did they come to this conclusion that there was uniformity in this one section - and that this is unique to human DNA?

What I think would be interesting (and, again, it may already have been done or proven) is to see what the cross homology among other species is. Is this DNA sequence, again, unique to only humans? Is it unique to mammals? Is it ubiquitous?

If anyone knows the answer, I'd seriously be interested in knowing as I think this is a critical piece of the information that may (or may not) have been reported.

-TT
 
Should anyone wish to find out their own ancestry, using y-chromosome or mitochondrial DNA, you might want to check this out-
 
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